Improvement in the manufacture of gunpowder



F. BU BNEY.

Patented Dec. 2,1873.

Manufacture ofunpnwder.

I n n Unrrnn STAT-ns PATENT Qrrrcn.

FREDERICK BURNEY, 0F FAVERSHAM, GREAT BRITAIN, ASSIGNOR TO THOMAS S. POPE. AND YVILLIAM S. COLVIN.

IMPROVEMENT I'N THE lilllANUFACT'URE OF GUNPOWDER.

Specification forming part of Letters Patent No. 145.4149, dated December 2, 1873; application filed 'y October-2, 1873.

To all whom it may concern:

Be it known that I, FnEDnnicKsBURNEY, of Faversham, .in the county of VKent and Kingdom of Great Britain, have invented an Improved Process of lllanufacturing Gunpowder, formed into regular grains of vlarge size, known as pebble 'gunpowdeig andf implements for the manufacture of the same, Of which the following is a specification:

This invention relates, first, to a process of manufacturing pebble gunpowder, being gunpower formed into gra-ins of large size;and, second, -to plate-molds for forming said grains. According to myinvention, I ,mold the meal or brokendown mill-cake receivedv from the amalgainating-inill int-o pebble powder at one operation, the powder being formed into grains of a .uniform size and shape. For this purpose I compress a layer of vbroken-down mill-cake between plates or molds worked by hydraulic or other pressure, bywhich the meal or broken-down mill-cake is condensed into uniform grains of the desired size. The plates forming each half o f the mold are made precisely alike, each being formed with a number of cells or recesses of uniform shape'and size. These cells are made angular in form, with inclined sides, to facilitatethe removal of the compressed powder. The cells cover the whole surface ef ythe plate or mold, without any intervening vflat surface, so that the whole of the pressure is exertedon the/powder inthe cells. In molding, the cells ofthe two platesl are made to coincide, one-half ofthe grain" into which the powder or mill-cake supplied to the mold is pressed being formed-by each plate. By this means gra-ins are made of angular form, (octahed'rens, for'ins'tance,') eaehcell in the plate forming one-half of the igure produced. Figurel shows atransverse section of aporticn of a pairi of the mold-plates sepa-rated' after having compressed the powder placed between them into grains, or pebbles, which are shownfas remaining in Athe cells of vthe 'flower plate. Fig. 2 is a plan, showing the cellular or honey-combed surface in whichpthe powder is molded, `the surfaces Iof thetwo plates being precisely alike. Figs. 3, '4, and 5, are plan views v'of mold-plates with cells of be abraded in packing.

different forms.v fFigs. 6, 7, 8, and 9 are views of separate grains ofpowder formed in said molds, respectively.

` A and B are the upper'adlowervmold-plates,

respectively.' They-are mounted in ahydraulic press, (not sh0wn,) 'the npper ,pla-te, A, beingv fixed by clamps around its bevelededges,

bolted to the head or top of the' press frame,-

and the lower plate, ,B, supported on the foll ower` .of the press, but without being fixed thereto, in a position exa'ctly parallel with the upper plate, A. The cellular surfaces of the two molds or platesface one another, and studs or pins are iixedon the follower for the plate B to abut against "when in position, and so makeA the cells in the two plates coincide ex-v actly when 'brought together. The plates are of metal, (preferably gun metal,) and are formed by casting in molds, each with' cells or molds of vuniform shape and size covering one siuface. These cells, Whetlier'square in plan, as shownfin Fig. 2, or of triangular, diamond, or hexagonal form, as shown in Figs. 3, 4, and

5, are so disposed closetogether that the wholesurface of the plate is occupied, the inclined sidesof contiguous cells meeting one anotherA at an angle, without any intervening Hat sur- 'face between the cells or around the edges,

the plates presenting the appearance of a honey-comb; The sides of the cells are inclined, to. facilitate thel removal of the compressed powder, and meet in anv apex at the center. The cells may, however, be slightly filled in, toround oft' or iiatten the apex ofthe grain or pebble, as sharp 'angles are liable to When the cells are made in the shape shown inFig. 2, the grain or' pebble of compressed powder will be in the form of an octahedron, as' shown in Figs. 1 and 6, the grains formed by plates having cells, asin Figs. 3,4, and 5, `being shown in Figs. 7, 8, and 9, respectively.

. The. operation is as follows: A supply of meal or brok-endown mill-cake is pla-ceden the lower o1" movable-plate B in a uniform 'layer'of suitable depth, according touthe'de- .grec of density required. The-saidpllfte B is then placed in position on the 'followerof the press, and, the two plates being then broughtclose together by the motion of the follower, pressure is exerted on the whole layer of milleake, which is compressed in the cells into the form of grains, one-half of every grain being formed in each plate. The plates are t-hen caused to recede, and, the plate B being withdrawn from the press, the compressed grains which remain thereon maybe removed. As the pla-tes do-not actually meet, the grains or pebbles will be sl ight-ly connected atthel edges; but they may be easily separated by hand, and are then ready to be glazed, as usual. Several pairs of mold-plates, each plate having a layer. of mill-cake between it, may be superposed on the pressfollower, and .simultaneouslycompressed at one stroke 'of the press, the plates being held in position and guided bythe pillars.. or frame-work of the press.

I am aware that pebble gunpowder has been manufactured by pressing meal powder into cylindrical holes in a mold-slab by means ot' cylindrical,plugs forced into said holes, thus forming; short cylindrical pellets or pebblesr but itis manifestthat this is a very slow and defective process, inasmuch a-s only so many .pellets or pebbles can be nia-de at oneopera- Aby Letters Patent, is-

1. The process herein described of molding; meal gunpowder or brokelrdown mill-cake into 4regular pebbles or grains ot' large size at one operation b v pressure between plates having cellular surfaces, substantially as described'.

2. Mold-plates with eellularsur'aces, the eells being shaped and arranged substantially as hereinbet'ore described, and for the purpose specified.

FH EDER'ICK BURNEY..

'itnesses:

'lnosjl LONGLEY, Gummi. Il murmura. 

